The gift of the first magi was gold, and though received by the babe, Jesus uses it in quite an interesting way.
To understand exactly why, we have to understand gold's value in the times in which Jesus lived. To the Roman world, gold was of very little value; almost all of the Roman coins were made of silver. When Jesus leads Peter to the coin in the fish's mouth, it is a silver coin. Because it was silver that had value for the Romans. But in the Temple...
In the Temple, gold had immense value. In the Temple, gold meant something. In fact, gold had come to mean so much in the Temple that in Matthew 23, Jesus curses the Pharisees for how much their gold meant to them. It meant so much, He says, that they thought it was the gold that gave the Temple its value.
So it is telling, then, that we don't see gold very often in Jesus's story; He does not want to give the impression, even in the slightest, that the gift of gold somehow makes Him valuable in the Temple.
But there is this beautiful parable that Jesus tells about a wealthy man who is going on a trip. The man takes his gold and gives it, in certain measure, to his servants. This is, of course, the parable of the talents, where the servants are rewarded based upon their faithfulness with the gold that they have been given. This is where we get the phrase, "Whoever is faithful with a little will be given more."
Jesus takes the gold that He has been given, which would likely have made Him a big deal ceremonially, and He spreads it around to His servants, giving them a stake in the most holy thing: worship. He takes what was meant to make Him a big deal, and He uses it to make us, the faithful, a big deal.
That's pretty cool.
And to the Pharisees who insisted that it was gold that made the Temple holy, that gave this ceremonial place its worth, Jesus makes here a bold statement that it is faithfulness that makes holiness, giving the servants His gold but rewarding their hearts, not their investments.
This is the only place in the Gospels where we see gold, and it's no accident. It is the gift of gold that is invested with the servants not because it is a representation of material wealth (if it were, He would have used silver), but because it is a concept of spiritual richness. Jesus isn't interested in making men wealthy; He is interested in making men holy.
He can only do that with gold.
Because gold has no earthly richness, not in ancient Rome; it only has ceremonial richness. It is only worth anything in men's holy places. Therefore, what a man does with his gold is a measure of how he stands in scared spaces. Well done, good and faithful servant. This....this is true wealth.
So if you want to know what happened to the gold from the manger, here it is, in this parable. It's the only place we find it in all the Gospels. Christ took the gift of gold and invested it in us, that we might show our faithfulness and become, good servants, the wealth of the Temple.